Panostotic fibrous dysplasia: A congenital disorder of bone with unusual facial appearance, bone fragility, hyperphosphatasemia, and hypophosphatemia

Abstract

We report a boy with unusual facial appearance, melanotic patches (“coast‐of‐Maine” type), myelofibrosis, recurrent femoral fractures, and widespread fibrous dysplasia of bone. Biochemical findings included raised serum alkaline phosphatase (bone isozyme) and 1,25‐(OH)₂ vitamin D, and low serum phosphorus levels. Elevated urinary excretion rates of total hydroxyproline, glycylproline, and γ‐carboxyglutamic acid indicated increased turnover of bone matrix. Transiliac bone biopsy showed a dearth of marrow elements, greatly increased bone turnover, and absence of normal trabecular organization. Serial radiographs showed progressive cortical thinning and loss of bony trabeculae. Calcitonin and etidronate treatments had no lasting effect on the progressive bone disease. The term “panostotic fibrous dysplasia” is suggested for this condition.